1. Field of the Invention
The present invention is broadly concerned with an improved oxygen dispensing apparatus of the type typically found in aircraft for supplying oxygen to passengers under emergency, reduced atmospheric conditions. More particularly, it is concerned with such apparatus which includes a relatively small, brightly colored flexible inflatable indicator element, preferably positioned within the confines of the primary oxygen supply chamber or bag, so that airline personnel can readily determine whether all passengers are receiving oxygen during an emergency.
2. Description of the Prior Art
A universal feature of passenger aircraft is the provision of stowed, overhead oxygen masks in the passenger compartment which are designed to drop within easy reach of the passengers in the event of a rapid depressurization of the aircraft. The passengers don these masks and are supplied with oxygen for a period permitting repressurization of the aircraft or safe landing.
It has been known in the past to provide various indicator devices associated with passenger oxygen masks, so that aircraft personnel can visually ascertain and confirm that all passengers are receiving oxygen. These devices have included in-line, rigid synthetic resin tubular bodies having an internal, shiftable flow indicator which moves to confirm oxygen flow. In addition, U.S. Pat. No. 4,098,271 describes an inflatable flow indicator device formed from peripherally sealed sheets as a subsection of the primary oxygen accumulation bag. The device described in this patent is deficient in that if a tear or aperture is present in the indicator section, oxygen flow to the passenger is lost.
There is accordingly a need in the art for an improved passenger oxygen mask having an inflatable, readily detectable indicator, but which will nevertheless supply oxygen to the user even in the event that the indicator structure becomes torn or otherwise unusable.